|Configuration of Non-Linear Digital Video Editing Systems
Revised March 2003
Revised Sept 4, 2003
Revised June 1, 2004
-Configuration of Non-Linear Digital Video Editing Systems-
By Charles F. McConathy
Even with the advent of faster dual processors, faster memory, faster busses, and faster disk drives, digital video, especially if it's uncompressed video, can still tax the best computers. Unless the computer system is properly configured, some or all of these components can become a bottleneck, resulting in dropped frames, corrupted data, freeze ups, out of sync audio, or other problems. This article is written to help video editors avoid these issues and to make good choices when configuring a video workstation.
Choice of Computer and Software:
Before selecting a computer system one should consider the following:
- Amount of budget available for computer purchase?
- Do I need portability?
- Will I be doing a lot of rendering?
- Will I be encoding content for DVD?
- Which operating system am I the most comfortable: Mac OS or Windows?
- Which video editing software package(s) fits my needs?
- Do I plan to work with uncompressed SD or HD video?
You will most likely want to go with a computer that supports the operating system, video editing software, and hardware that you are the most comfortable. Remember that computers are constantly changing. The computer itself will probably be the first component in your system to become outdated. In making a choice, go with a high-end or dual processor model since it will serve you the longest. It is wise to upgrade or purchase a new computer system when it is needed since they can become outdated rather quickly. Remember that there will be faster computers around the corner; this does not mean the one you bought is not of value. Don't look back; use it as long as it serves your purpose.
If a Macintosh computer is your choice we suggest you consider a dual processor model. We believe you will keep a dual processor computer longer than a single, especially since many video applications are multi-processor aware. Mac OS X also exploits dual processors to improve performance. If your projects include a lot of rendering a dual processor is an excellent choice since it will save you much time. The G5's "Altivec" or "Velocity Engine" also boosts rendering speed and accelerates Photoshop considerably - especially with a Macintosh G5/2.0 DP or greater.
Choosing a model with a SuperDrive for DVD authoring is a good choice. A second computer or a large flat panel monitor speeds the editing process since you can have longer time lines and have more pallets and bins open at the same time.
If you need portability consider a PowerBook. They work well with Final Cut Pro and Avid Xpress Pro. The FireWire port of the PowerBook is excellent and works with DV camcorders/decks and FireWire hard disk drives.
Purchase a Laptop or PowerBook for portability reasons, not as a substitute for a desktop workstation. Desktops are less costly to configure, especially when it comes to storage, and they readily support larger displays, real-time and uncompressed hardware.
If your budget is tight you might consider an iMac with a FireWire port. For additional storage use FireWire disk drives. Final Cut Pro works fine with an iMac. iMac's are not as productive since they have smaller displays and slower processors, but make a good entry-level system. The only thing is an iMac does not allow you to install internal storage and the built-in monitor is a bit small for productivity.
Many ask if it's worth it to upgrade an older Macintosh with a faster CPU. Generally the answer is no, especially when building a video editing station. Processor upgrades are expensive, consuming funds that could go toward a new computer with new warranty, faster drives, faster internal cache, speedier memory busses, etc. Improving the speed of a processor does not cure other internal bottlenecks. Upgrading a processor often creates a system that is unstable due to mismatched parts. We think it's best to re-purpose the old computer or sell it, and take the upgrade cost and apply it towards a new computer.
If your choice of computers is a PC, consider one of the faster models that are housed in a cabinet with plenty of room for installing multiple SATA disk drives and enough fans for good air management (needed to cool the disk drives).
Picking a motherboard with compatible BIOS and a VGA display card is very important. Not all motherboards are created equal. Many NLE software and hardware vendors list known compatible motherboards, BIOSes, and VGA cards on their websites.
CD-RW, floppy, and DVD-R drives can be added internally to a PC. Choose an approved FireWire OHCI PCI card and if needed an ATA-133 PCI or Serial ATA card to support additional disk drives. We suggest that you use only Windows XP Pro and to go with applications and hardware supported by this operating system.
Picking a PC laptop is not as easy as a desktop system. Some PC laptops have excellent FireWire ports but poor video display technology, which means they might capture video, but could drop frames on playback. It is best to purchase only models that have been approved by the publisher of the software you expect to use.
Choice of Computer Monitors:
Flat panel monitors are quickly dropping in price and improving in quality. They take less room, consume less power, and are much easier to move. We suggest you consider a 17-inch flat panel monitor as a minimum. However, a 19-inch CRT monitor will cost about one third that of a 17 inch flat panel. A pair of 19-inch CRT monitors can be installed at less cost than a single 17-inch flat panel and will be much more productive. If your budget allows an Apple Cinema 20 or 23-inch flat panel is an excellent choice.
There are three different display connectors analog VGA, and digital DVI and ADC, with ADC on Apple computers only. Most CRT monitors are VGA. Flat panel monitors come as VGA and/or DVI, and Apple's latest are ADC only (ADC is essentially DVI with additional connections for monitor power and USB). The new Power Macintosh computers ship with both a DVI and an ADC connector with an adapter to VGA. There are DVI to ADC converters that include power, and ADC to DVI adapters is also available. There are even adapters for using ADC monitors on PCs. Dual-display VGA host adapters for Macintosh and PCs are available so you can have two monitors without giving up a PCI slot for a second monitor card.
Storage and RAID Considerations:
Picking the storage that fits the type of editing you plan to do is very important, and making the right choice can save you hundreds of dollars. Some want to start out with SCSI when in fact Parallel ATA (PATA) or Serial ATA (SATA) internal or external drives are more than enough. PATA and SATA technology has come long way and can be a good choice especially for DV and even SD editing. ProMax has developed SATAMAXi and SATAMAXe systems. The SATAMAXi/Mac allows you to have five internal drives in the current Macintosh G5. This way you can dedicate four of the drives striped as RAID-0 and the one as a boot drive. Similar systems for Windows based computers are available as well. The SATAMAXe allows four SATA drives to be installed externally for use with Macintosh or Windows. SATA storage is much less costly than SCSI and does a great job when properly configured.
It is imperative that disk drives run within temperature specifications and be connected to quality cables and connectors for error free transfers. Use quality cables, quality connectors, and make sure air management is good enough to keep the hard disk drives cool. Drives that run at higher temperatures not only shorten their useful life but generate more errors. The internal chamber of a disk drive must maintain a given level of relative humidity in order for the heads to fly properly. If the drives get too hot, the relative humidity drops, making it more difficult for the heads to stay on track, resulting in retries. During these extra spins the drive's buffer is not being refilled with data, possibly resulting in dropped frames.
If the wrong types of cables or connectors are used they can be a source of errors and can lead to data corruption. The choice of cable technology is very important. For ATA drives, we suggest only 80 pin ATA-100 cables that include a ground line between each data line for optimum performance and few if any errors.
Parallel ATA vs. SCSI:
PATA drive technology has improved over the years and has replaced SCSI in many applications due to their lower cost and improved performance. PATA technology was designed for use with short cables (about 17 inches) inside the computer cabinet, while SCSI supports longer cables making it good for external storage and for high performance RAID systems. Serial ATA allows for one-meter cables what has made it possible to create high-speed external disk arrays.
Parallel ATA (PATA) or what has been called ATA:
If you plan on editing using DV or DVCAM as your source, 7200-RPM PATA Ultra DMA drives offer plenty of bandwidth. There is no need to consider a RAID storage system. A single PATA-133 disk drive connected to an ATA-66 or ATA-100 port will sustain 35 MB/sec reads and high as 45 MB/sec writes. DV and DVCAM use only 3.6 MB/sec and will run clean with a minimum sustain rate of 7 MB/sec.
Serial ATA (SATA):
What is Serial-ATA (SATA) and why was it developed?
SATA is an evolutionary replacement for the existing Parallel-ATA (PATA) data storage interface. SATA is scalable and allows for future enhancements. SATA is a drop-in solution in that it is compatible with today's software, which will run without modification. It provides cables that are simpler to route and install, smaller cable connectors, and lower voltages not possible with PATA.
Will there still be PATA when SATA is readily available?
There will be a window of time where both PATA and SATA will be available. Many expect that within a couple of years that SATA will dominate. Apple's G5 computers come with 2 SATA ports. Some PC motherboards come with both PATA and SATA ports. SATA PCI cards for Windows are available now with up to eight ports. This means that 2 TB of cost effective storage can be installed in a computer or server. Soon over 3 TB will be possible.
What are the benefits of SATA?
End users will benefit with easy upgrades to their storage. Configuration of SATA devices will be much simpler, with no requirements of jumper and settings.
- A 150 MB/sec interface rate (not to be confused with the data rate of a single drive)
- Enhanced data reliability
- Longer and thinner cables up to one meter or about 3 feet
- Snap-in like connectors
- No master/slave jumpers to set
- Master only will improve performance of striped hard disk drive pairs
- Latency more like that of SCSI thus RAID-0 to be much faster than PATA
What is the cost to implement SATA in a system?
The cost of SATA will start out somewhat more expensive than PATA but will rapidly drop to the same cost as PATA.
Beyond hard disks, will SATA be used on, optical drives, DVD, and ZIP drives?
SATA supports all ATA and ATAPI devices, including CDs, DVDs, tapes devices, high capacity removable devices, zip drives, and CD-RWs.
What are some compelling reasons why SATA is a viable?
- Price: SATA was created, with desktop prices in mind, as a replacement for PATA. Initial hard disk drives are expected to be priced competitively for the desktop.
- Cabling: SATA employs a thin, point-to-point connection, which allows for easy cable routing within a system. This avoids master/slave, "daisy-chaining", and termination issues. Also, better airflow can be realized compared to systems with wider ribbon cables.
- Performance: The first SATA bus technology can deliver as much as 1.5 Gbps (150 MB/sec) of performance to each drive within a disk drive array and migrating to 3.0 gigabits per second (300 MB/s), then to 6.0 gigabits per second (600 MB/s). This roadmap supports up to 10 years of storage evolution. The maximum rate of PATA drives today is about 72 MB/sec. But remember this is the bus rate and should not be confused with the data rate of a single PATA or SATA disk drive. The choke point remains the disk drive not the bus. A single PATA or SATA drive will remain about 35 to 45 MB/sec. With SATA multiple disk drives can be striped with performance near that of SCSI.
So you see, 35 to 45 MB/sec from current PATA or SATA technology is more than enough for DV and DVCAM. However, single PATA or SATA disk drives do not produce high enough sustained rates for uncompressed SD video.
At ProMax we avoid 5400-RPM hard disk drives especially when used with long video projects, where disk fragmentation and complex areas on the timeline can be a source of dropped frames. Adding multiple audio tracks can also cause dropped frames since each audio track becomes a separate file, causing latency issues during head movement. (Audio creates latency issues, whereas video is more I/O intensive.) With one track of video plus four tracks of audio with cross fades, you have created nine separate files on the drives. Now add titles, transitions, and effects, all of which add more files. These parts of the timeline can become very complex and can result in dropped frames during playback.
We suggest PATA-133 or SATA; 7200 RPM drives that are field proven. Hatachi/IBM drives have the best microcode for controlling the drive, and the best electronics allowing longer PATA cables than other brands. Longer PATA cables are often needed for installing multiple drives in a computer. With SATA you can have up to one-meter cables.
At ProMax we avoid certain brands of disk drives such as Maxtor due to their heavy failure rates and errors, as reported on video forums such as www.2-pop.com and DV-L. Note that not everybody has trouble with Maxtor drives. However, for most people their data is very important. We stay with tried and proven components as insurance.
If you are installing PATA storage in one of the mirror faced G4's we have discovered that you can install 4 additional ATA drives and still keep the original boot drive - as well as a DVD-R (SuperDrive) or a CDRW (Combo) drive. In this case the boot drive is mounted with side brackets in the lower optical bay and is connected to a special cable that is connected to the ATA-33 port on the motherboard and feeds the top bay optical drive as well. Four additional low profile hard disk drives can be added by placing two in the factory-mounting bracket on the right and two in the factory-mounting bracket under the optical drive enclosure. Data cables and power are provided by Apple for the four drives. There are three ATA ports on these motherboards ATA-33 for optical drive. The ATA-66 and ATA-100 are for use with disk drives. We find excellent performance from both the ATA-66 and ATA-100 ports. In fact with OS X you can stripe these four drives and get data rates high enough for Standard Definition with Real-time previews using the AJA Kona SD card. It is best to connect the boot drive to a PCI ATA-133 card to speed opening of applications, etc.
If you are installing internal storage in the new G5's you are limited to one data drive which means you must go externally for additional storage. ProMax is developing cost effective external SATA storage with two and four removable drives.
FireWire Storage Systems:
FireWire disk storage is becoming very popular, especially for those who do not have room internally for adding additional storage, as on a laptop or PowerBook computer. FireWire drives are also excellent for moving large amounts of video data between computer stations.
Like early SCSI storage, FireWire drives have had their issues. Second generation bridge Chips have improved performance and compatibility. FireWire drives are nothing more than ATA drives converted to FireWire via a bridge. Early on these bridges were bottlenecks. With the new Oxford 911 bridge, transfer rates from 35 to 45 MB/sec is possible. These rates are more than enough for DV/DVCAM video editing. One should be aware that picking a FireWire drive with an Oxford 911 bridge is only a part of the choice. Not all cabinets are created equal, nor are all bridges and device drivers. Cabinets with internal power supplies tend to work better than those with wall mounted supplies.
Be aware of differences in FireWire cables. Well-shielded cables are imperative. They should be no longer than the IEEE spec of 4.5 meters. Don't plan on daisy chaining more than two or three on the same bus, and it works best if all the drives employ the same bridge technology. Mixing FireWire disk drives and deck/camcorders on the same bus can be tricky. If problems occur, changing the position of the devices in the FireWire chain or trying different lengths of cables can help.
FireWire 800 ports are now included on new Apple computers. FireWire 800 disk drives have started to appear that employ the Oxford 922 bridge technology. FireWire 800 uses a 9-pin connector, which should be more reliable and cause fewer problems. FireWire 800 data rates are not much faster than FireWire 400 since the choke point is the drive not the bus. Remember the limiting factor is the read/write channel of disk drives not the interface. In time drives will be faster as higher density disk drives come to market.
PATA to SCSI Storage Systems:
Medéa, Huge and other companies build storage systems that use less costly PATA drives converted to SCSI. These drives need a PCI SCSI Host Adapter. They are less costly than SCSI to SCSI. If the system supports Ultra SCSI 160 connections they can sustain from 65 to 95 MB/sec. These systems use hardware RAID-0 or RAID-3 with large buffers dedicated to each drive. These drive systems are excellent for DV/DVCAM and uncompressed standard-definition real-time video
SCSI to SCSI RAID Storage Systems:
SCSI is about twice the cost of PATA/SATA storage. Ultra SCSI 160 or 320 is best used for uncompressed SD/RT and HD video systems. For high-demand RAID storage, SCSI technology is best since it imposes minimum overhead during the connect-burst/ disconnect/connect-burst routine of RAID-0. The recent introduction of the Apple Xserve RAID, which employs Fibre Channel to PATA, makes it an excellent choice for high-demand applications and is much cheaper than SCSI RAID systems. The Xserve RAID is 2 Gb Fibre Channel, dual channel hardware controllers capable of RAID-0, -1, -3, -5, as well as -30 and -50. It is easy to connect and maintain and can be setup as true SAN with optical cables as long as 100 meters. SCSI cables have to be reasonably short, so storage systems must be installed within a few feet of the workstation. For some, however, this is not acceptable due the noise the drives and fans make.
At ProMax, if one is going to go with SCSI, we recommend eight LVD 320 drives striped as RAID-0, as four and four on each channel of a dual channel Ultra 160 or 320 PCI host adapter. We recommend disk drives that include an 8 or 16 MB buffer, as these are especially good for SD/RT and HD applications.
Many have asked if adding a high performance RAID storage system to a DV/DVCAM workstation will improve functions like rendering. The answer is no, it's a waste of budget. Rendering is computer intensive, not I/O intensive. DV/DVCAM uses only 3.6 MB/sec thus adding a RAID system with high-sustained rates is overkill.
We think that SCA (80 pin Single-Connector-Attachment) drives in removable bays are superior to fixed 68 pin drives. The reason is that replacing a drive is very easy. Removing disk drives from the cabinet and packing them in foam before shipment keeps them safe. A cabinet with 8 to 15 internal fixed drives is very heavy and hard to ship without damaging the drives and the cabinet.
SATA Storage Systems:
ProMax has developed cost effective external SATA storage especially for the G5's. The systems include 2 or 4 removable drives that can be striped as RAID-0 to serve DV, DVCAM, SD, and SD/RT.
Choosing a Storage System:
It's not a matter of if, but when, your hard disk drive(s) or computer hardware will fail. Even the best hardware comes with an MTBF (mean time between failure) rating. One of the most common failures is with disk drives. While there have been many technology improvements by disk drive manufacturers such as rapid positioning of heads to a zero position on normal power down but not all disk drives have this technology. Heat is also a major cause of hard disk failure. Other failures come from blocked fans, bad cables and connectors, and inadequate cooling which can shorten the life span of hard disk drive(s). When handling a bare hard disk drive do not touch the data connector or any component on the printed circuit board.
Another source of disk drive failures can be during power-on when restarting a computer before the drives have stopped spinning from a shutdown. This can cause components to burn out and fail because of a voltage spike caused by residual voltage in the circuits. To minimize hard disk drive problems one must recognize some of the most common reasons that disk drives fail and try to prevent them. Like something as simple as the 10- second rule - No computer or hard disk drive system may be turned on again before 10 seconds has passed from the time the unit was turned off. This gives adequate time for all parts to fully discharge which will lessen power stress when powering the drive(s) or computer system back on.
It is wise to use a power-conditioning device to lessen the chance of surges especially in areas that are prone to electrical storms or where the voltage varies a lot. Also some buildings are not wired with ground return lines to the electrical panel which can be a source component failures and the loss of data.
For DV editing via FireWire the most cost-effective storage is internal PATA or SATA hard disk drives. Modern drives produce as much as 45 MB/sec, which is far beyond the 3.6 MB/sec that DV consumes. And there is no need to stripe PATA drives as RAID-0 for added performance. If one drive fails in a RAID-0 all data is lost.
Other than following preventive measures here are some ways to protect your data. One way is to use tape backup. The only thing with tape back up of large amounts of video data is that it takes a lot of time and the data set is changing frequently making it all most impossible to use tape for backup. Some editors have resorted to using removable or FireWire hard disk drives to backup data since the price of storage has dropped and takes much less time than tape. Also there is no restore time should loss of data take place. Use of removable or FireWire disk drives to archive projects is becoming popular as well.
Many people ask if mirroring is practical with non-linear video editing systems. There are several potential problems with mirroring. Mirrored systems replicate bad data as well as good data. One of the most common causes of data loss is software failure or human error. A mirrored system will replicate the error. Another drawback to mirroring is their cost-effectiveness even with the lower price of disk drives. A mirrored drive(s) cost as much as the primary drive(s). Also most software RAID-1 or mirrored drive systems will not have high enough sustained 'Write" rate to capture video due to the fact that the data must be written twice which cuts the "Write" rate in half.
For data protection hardware RAID-3 or -5 is a better choice than RAID-1 mirroring. RAID-3 or -5 is less expensive requiring about 20% premium in disk costs while providing the same level of data protection. If a drive fails in a RAID-3 or 5 configuration there is enough redundancy to deliver the information from the remaining disk drives.
Although RAID-3 or -5 is more cost-effective but it does have an additional cost such as enclosures and a SCSI host adapter. Low cost ATA-to-SCSI RAID-3 storage systems are becoming very affordable. They are an excellent solution for disk drive fail-over.
It's a good idea to keep spare disk drives on-site. This may seem obvious to most yet many people using RAID-3 or -5 do not have adequate replacement drives to cover drive failures. These spare drives should be of the same capacity so that a proper rebuild can take place after a failed drive is replaced.
Problems Associated With SCSI RAID:
RAID crashes occur for various reasons including the following:
- Cable failure, resulting in data getting scrambled.
- A replacement drive installed with the wrong SCSI ID.
- A disk drive fails. User pulls out a good drive rather than the faulty one causing the
RAID system to become irreversibly corrupted.
- Replacement drive is a different size than the other drives in the RAID-set causing
problems with rebuilds.
In short RAID is not a 100% solution to solve data loss. Other types of hardware failure may affect your data such as bad memory module, a bad cable, or a bad supply.
How do you decide if you need a RAID solution?
Consider these factors:
- The cost of lost data - How important is your data?
- Critical data-protection window. This is the interval of time elapsing between your
last backup and time of a crash. The longer this interval, the more costly the loss.
- Determine the amount of data you can afford to lose.
- Bare-metal recovery is very costly and takes time.
RAID-0 adds performance by striping the data across two or more drives, reducing the workload for each individual drive. RAID-0 is often done with software, but hardware RAID-0 is better especially if the hardware adds additional memory buffers for each drive. Note however that RAID-0 offers no redundancy: if one drive crashes, all the RAID's data is lost.
RAID-1 mirrors one set of drives to a second set. The problem with mirroring is that it takes twice the time for each write since the data must be written twice. And mirroring is expensive since you need twice the amount of drives. RAID-1 thus provides redundancy for reliability purposes, but at the expense of performance, although hardware RAID-1 controllers minimize the penalty.
RAID-3 and 5 stripes data over multiple drives, perhaps 4, 5, 6, or more. One drive is a "parity drive" providing redundancy, thus you "lose" storage space equivalent to one drive. If any single drive fails, you replace it and the system rebuilds the data on it. Some systems take a lot of time to rebuild especially if done while the storage system is under use. Some RAID-3 and 5 systems have very fast reads with slower writes, since it takes time to scatter the data over multiple drives. Other systems have overcome this with special hardware.
You need to determine which RAID system best fits your requirements. Don't just take the word of manufacture with published data rates, but try to get real-world results from other users. Benchmarks don't always tell the whole story. An old timer in the storage industry once said, "there are liars, damn liars, and benchmark liars!"
Some companies quote the data rate of the storage interface, like Ultra 160 as 160MB/sec or Ultra 320 as 320 MB/sec. No single drive can sustain these rates: it's the burst rate, not a sustained rate. To get a sustained 160 MB/sec you typically need 8 drives striped as RAID-0 across a dual channel host adapter.
Fibre Channel RAID Storage Systems:
Early Fibre Channel was based on one-Gigabit technology. Two-Gigabit Fibre Channel systems with data rates high as 200 MB/sec. These are excellent for use in editing SD/RT and HD video. It is possible to mix 1-Gbit and 2-Gbit Fibre technology, but the results will be performance at the 1-Gbit level. Optical Fibre Channel cables can be 100s of meters long, so noisy storage cabinets can be placed in a machine room away from the edit suite. Fibre Channel storage can be configured to safely share files with multiple workstations in a SAN (Storage-Area Network) configuration, though the ease and flexibility of this sharing varies by vendor.
Added productivity is a key consideration when choosing a Fibre Channel SAN that often has fast payback. Fibre Channel SANs are best suited where multiple editors need to share the video data in order to finish large projects in a timely manner.
Much study must be made before installing a Fibre Channel disk array. Take care in picking the right host adapters, cables, software, and switches before ordering. Switches are expensive but are highly necessary. A switch isolates each station from the others, guaranteeing uninterrupted bandwidth. Also the switch protects each station from "LIP"(Loop Initialization Process). LIP is the process of polling the Fibre Channel bus each time a workstation starts up, which interrupts data transfers for a split second. During LIP dropped frames will take place on active workstations, which is eliminated with a Fibre Channel switch.
Apple Xserve RAID - Fibre Channel Storage System
Apple's Xserve RAID, a high-performance storage system that delivers data protection and enormous capacity of up to 3.5 TB at a groundbreaking price. The innovative Apple-designed Xserve RAID architecture combines affordable, high capacity PATA drive technology with a dual independent 2 Gb Fibre Channel host inter-face for fast, reliable data access. Each 250 GB Apple Drive Module uses a dedicated drive channel, maximizing the 400 MB/s Fibre Channel host connection. This also means that as you add drives, Xserve RAID scales in both capacity and performance. And by adding more systems, you'll have virtually limitless expansion. High-speed throughput comes from dual independent 2Gb Fibre Channel host interface with data rates at up to 400 MB/s - fast enough for demanding HD video editing. High-availability architecture and dual independent RAID controllers support RAID levels 0, 1, 3, 5, 30, and 50.
Current Suggested Retail Prices:
1.0 TB Xserve RAID - with 4-250 GB Modules $ 5,999
1.75 TB Xserve RAID - with 7-250 GB Modules $ 7,499
3.5 TB Xserve RAID - with 14-250 GB Modules $10,999
Apple Fibre Channel 2Gb PCI Card -w/Two Cables $ 499
250 GB Drive Modules - Xserve or Xserve RAID $ 499
Even as a stand along - point to point - storage system Xserve RAID is much cheaper than going with a SCSI to SCSI software RAID-0 system. For example: A 19-in rack filled with 10 - 146 GB - LVD 320 disk drives for total of 1.46 TB - sells for as much as $15,999 and more. The system is software RAID with no data protection and short SCSI cables. The Xserve RAID offers more features, is much easier to install and maintain, easier to expand, offers more reliability, and is SAN capable making it an excellent choice.
The cost of memory is at an all time low. The minimum we suggest is 768 MB or better yet 1024 MB or more. Not all RAM is created equal, so make sure you pick a known proven source when purchasing RAM. Be sure to handle memory by its edge and ground yourself before installing modules. Do not touch the contacts or parts on the SIMM. This could cause damage that might not show up for months. Some low cost RAM modules are made using mismatched parts, which can become source of errors that can be hard to isolate. G4's and G5's use DDR technology and require PC-2100 or PC-2700 memory.
Conflict Catcher, Virex, and other such utilities can cause conflicts when used with video editing systems. It is best to create a complete set of Extensions and then by trial and error eliminate troublesome extensions if conflicts become a problem. Sherlock's indexing feature (on Macs) and Microsoft Office's FindFast indexer can bog a machine down and should be turned off while editing. Appletalk networking, especially on slower Macs, can also cause dropped frames or interrupted playback.
Partitioning Data and Boot Drives:
It is best to run video editing applications from their own boot partition and to keep that partition (and computer memory) free of applications such as web browsers or games that are memory and CPU-hungry. It's OK to run web browsers and such from their own boot partition (remember that even if they aren't being run, installing such applications on your video partition can add extensions or services that run in the background, reducing the efficiency of your machine). AfterEffects, Photoshop, Commotion, and other video editing applications can be installed in the video partition.
Large data drives do not have to be partitioned. It might be advisable to partition large data drives especially if your projects are small and you work more than one at the same time. The reason is that it is advisable to start each new project on a freshly erased partition. If you partition a large drive you can erase any partition without harming data on the other partitions. Erasing clears the directory; thus no fragmentation is left on the partition.
Backing up large disk storage takes a great deal of time even with the best backup devices. With video editing the data set is constantly changing, making it even more difficult since even if one wanted to there might not be enough down time to perform a backup. And remember that it takes as much time to restore as it does to backup.
Many editors simply keep their EDLs and project files backed up on a CD, ZIP disk, or a floppy, and keep the original videotapes. It's also a good idea to keep graphics, titles, and other files that take only a small amount of room, but take a lot of time to create, on ZIP disks or other removable media as well. By doing so, should a failure take place, getting a project going again will take much less time.
Adding a Digital Video Source Deck or Camcorder?
Many people begin editing using their camcorder as a deck. However, once an editor uses a deck like a Sony DSR-11 he or she will never want to use a camcorder as an editing deck again. Why? A camcorder transport is slow. With a camcorder it will take a lot more time to log a series of tapes, and you're placing additional wear on its heads.
A DSR-11 will rewind a 60-minute miniDV tape about 3 times as fast as camcorder and will record and play standard size tapes up to 3 hours. In fact, if you place a 3-hour DVCAM tape in a DSR-11 and set it to record DV, you can record 4.5 hours on it. If your budget allows a deck you will not be sorry, since your productivity will be much higher than when using a camcorder. Note that some of the less costly walkman-style decks have camcorder transports, so will not be as productive as a DSR-11, DSR-25, DSR-45,or other professional decks.
Q: Can I use an older computer to build a video editing system?
A: Yes but be aware of the bottlenecks and conflicts when attempting to use an older computer.
Q: Can I use an older computer such as a Beige G3/266 or Power Macintosh?
A: Yes but you will need to select a compatible PCI FireWire card and storage along with compatible Mac OS, QuickTime, and FireWire drivers. And be aware that the newer G5's are many times faster, and the built-in FireWire ports tend to be more trouble-free and more compatible than those on a PCI card.
Q: Do I need SCSI storage for DV/DVCAM editing?
A: No PATA/SATA or FireWire drives are satisfactory.
Q: What is the best way to convert Hi8 to DV/DVCAM?
A: Copying a Hi8 or SVHS analog source via S-Video to a DV/DVCAM deck offers very acceptable results. Often the digital copy looks better than the original since the DV decks comb filter eliminates noise. New time code will be created on the digital tape, which can be used for batch capture. Some decks offer E-E direct analog to FireWire conversion without making a copy, so you can capture the analog video directly (although without its timecode). Sony, Canopus, and other companies make converter boxes that take S-Video or Composite along with RCA audio connections and transcode to DV over FireWire.
Q: Can I make BetaSP dubs to DVCAM with Time Code?
A: Yes Excellent quality dubs can be made with a properly equipped BetaSP deck like a UVW-1800 or BVW-75 and a DVCAM deck like a DSR-80 or DSR-1800 via component YUV and balanced audio connections. For direct input into DV/DVCAM editors, it's also possible to use media converters such as the ProMax DA-MAX+ or ProMedia Converter (PMC) with the following connections: component, S-Video, composite, balanced and unbalanced audio, and FireWire ports. The DA-MAX+ and PMC also converts FireWire machine control to RS-422 Sony protocol, so you can control a BetaSP deck and transfer its TC as well.
Q: Why do some want to work with uncompressed video using AJA Kona or Pinnacle CineWave cards instead of DV via FireWire?
A: Simply put, uncompressed video offers 4:2:2 color sampling instead of DV's 4:1:1which means that chroma-keying is easier. Also, added graphics, text, and animation will not have edge problems and will end up much cleaner with uncompressed video, without needing careful filtering and preprocessing.
Copyright 2003 by ProMax Systems, Inc., Irvine, California.
Permission is granted to republish as long as no alterations are made and the copyright notice is included.
By Charles F. McConathy, President
ProMax Systems, Inc.
16 Technology Drive - #106
Irvine, California 92618
Irvine: TEL: 949-727-3977 o SALES: 1-800-977-6629 o FAX: 949-727-3546 EMAIL: firstname.lastname@example.org or email@example.com
Web Page: www.promax.com
About Charles F. McConathy
Charles F. McConathy is the President and CEO of ProMax Systems, Inc which is a leading provider of Turnkey solutions for NLE workstations. You can contact Charles at firstname.lastname@example.org